Domain name system (DNS) records store important information about domains and hostnames. These records hold different types of information, such as the IP address of a website’s server, the email server associated with a domain, or information about the website’s security protocols, that are necessary for routing internet traffic to its intended destination.
They function like maps, directing DNS queries, or requests for information about a domain name or hostname, to the desired endpoint.
DNS records, also called zone files, live in authoritative nameservers. The information they contain exists in text files written in DNS syntax, a language composed of a string of characters that tells a DNS server how to do DNS queries. Some examples of what DNS syntax can instruct a DNS server to do include:
- Directing traffic to a specific IP address associated with a domain name
- Set up email service for a domain name by specifying the email server’s location
- Implement security measures by specifying the appropriate certificates
Every domain needs at least a few DNS records to allow users to access the website using the domain name. You can perform a DNS record lookup to check the records of any site.
The most common record type is an A record, which indicates a given domain's internet protocol (IP) address. Without A records, users must manually type in a website’s IP address for the site to load.
When a site has a subdomain like discourse.webflow.com, the subdomain will often have a DNS CNAME record that points to a root domain (webflow.com). This feature allows the host IP address to change without affecting a user’s bookmarks.